You mite try Craigs list,,Im not seein any takers here,,

You know, every now & then someone tries something new, kinda radical & it works out,, sometimes, its just a bust,,Bummer this one cost ya so much,
What was the goal? TRying for a discrete battery installation to clear up some room on the bike? I think there have been a coupla brave souls who have done that. I cant remember what battery they went with. If I was gonna do that, Id want either a manual decomp or an electrical over ride so I could hold the exhaust valve open long enough to really l;et the starter get that engine rollin before I let it hit the compression stroke, & that just mite not get it, either,, if it didnt fire rite off, youd need to hit the decomp again & let it get another run at it, I thot about the smaller battery & all,, but the hassles seemed to ouweigh any potential feeling of sense of accomplishment I mite get,, so, I stuck with stock stuff.,.
Whats your next plan of attack? Gonna see if you can find a better Mini or you goin stock lead/acid or Glass Mat?

just bought one of those YTZ7S batteries as those seem to do well for people, The Evo 4 cell just didn't seem to have enough to kick the starter over and fire the plug together for a good solid start. Stock batt hits it on the first roll over.

If the YTZ7S wont do it either I will just go with a big crank we will see.

These should be A123 cells and the pack is good for 13.2v
the problem is they are only rated for 2.3 amp hrs

Honestly, I'm really surprised the 4-cell worked at all. Even the 8-cell isn't rated for an engine this big, especially not a single. And that battery is garbage now, you've surely over-heated the crap out of it and drained it too far below it's discharge voltage. Now that battery is just a hazard and will eventually start expanding in size and then burst. I can't believe you'd really try selling this.